The size of the Nova class

The Nova class was a type of Federation starship designed for short-term planetary research missions. It was placed in service starting in the late 24th century.

To calculate the size I first had a look at the MSD (Master Situation Display).

Nova class side view by Starship Collection

According to this MSD the ship has 8 decks and a intermediate deck on the edge of the saucer section. There are 4 decks - the intermediate deck - and another 4 decks.

• The premise for all my deck calculations: a deck is 2.5m + 0.5m for EPS cables, power cables, ... = 3m height for a deck. 
• My calculations follow a purely mathematical approach. I do not compare bridge modules or disk heights with each other. I always pull in decks based on the rows of windows and then calculate a physically plausible room height.

The height of the decks on the MSD is different (which isn't plausible). Therefore, the MSD doesn't quite fit the external appearance of the spaceship. But if you give the intermediate deck a little more space (normal deck high), it fits better with the rows of windows.

schematic by Starship Collection

With a deck height of 3m, this results in a total length of 172m for the Nova class.

The Nova class variant (USS Rhode Island under command of Captain Harry Kim) is a litte bit longer because of the different Deflector area at the front.

schematic by Starship Collection

With a deck height of 3m, this results in a total length of 175.2m.

Design problems:

• As with other Starfleet ships, there is a difference in height at the shuttle bay. I solved this with a half deck, also to be able to correctly include the construction of the rear observation lounge as a deck.
• With the original MSD, it seems not plausible why there is an intermediate deck after 4 decks that is extremely flat.
• Rick Sternbach on the planned size: "I drew the blueprints at 1"=30', and the ship is 24.25" long, so the real thing would be 727.5 feet or 221.74 meters". [drexfiles.wordpress.com] -> A length of 225m can only be achieved if a deck height of 4 m is assumed.